CYSTICERCOSIS. 



291 



erroneous idea that the pork-measle tapeworm occurs in dogs as well 

 as in man. 



Life history. In tracing the life history it is best to begin with the 



Fig. 137. — Small and large hooks of (A) Tcenia marginata, (B) T. serratn, and (C) 

 T. ca'Hurus. a, Small hooks ; h, large hooks, x 480. (After Deffke.) 



egg, produced by the adult tapeworm in the intestine of dogs. These 

 eggs, containing a six-hooked embryo, escape from the dog with the 



Fig. 138. — Sexually mature segment of the marginate tapeworm {Tirnia marginata). 

 cp, Cirrus pouch ; gp, genitpJ pore ; n, nerve ; ov, ovary ; sg, shell gland ; t, testicles 

 tc, transverse canal; id, uterus; v, vagina; vc, ventral canal; vd, vas deferens: 

 vg, vitellogene gland. Enlarged. (After Deffke.) 



u 2 



